Process for forming trilobal yarns

ABSTRACT

THE INVENTION DISCLOSES A SPINNERET FOR PRODUCING A TRILOBAL FILAMENT, AND FILAMENTS PRODUCED USING SUCH SPINNERET. THE SHAPE OF EACH ORIFICE OF THE SPINNERET CAN BE CONSIDERED AS BEING PRODUCED BY A CIRCULAR APERTURE, DIAMETER D INTO WHICH PROJECT AT 120* INTERVALS, THREE IDENTICAL TRIANGULAR PORTIONS, SIDES OF THE TRIANGLES BEING TANGENT TO ONE OR MORE COAXIAL CIRCLES HAVING A DIAMETER BETWEEN 1/6 AND 1/3 OD D, THE ANGLE AT THE APEX OF EACH TRIANGEL BEING BETWEEN 60 AND 100*.

3, 1971 JEAN-LOUIS JACQUINET 3,579,525

PROCESS FOR FORMING TRILOBAL YARNS Filed Sept. 27, 1967 2 Sheets-Sheet 1tlorney,

May 1 1971 JEAN-LOUIS JACQUINET 3,579,525

PROCESS FOR FORMING TRILOBAL YARNS Filed Sept. 2'7, 1967 2 Sheets-Sheet2 I nvanlor United States Patent 3,579,625 PROCESS FOR FORMING TRILOBALYARNS Jean-Louis Jacquinet, Lyon, Rhone, France, assignor to SocitRhodiaceta Filed Sept. 27, 1967, Ser. No. 670,862 Claims priority,application France, Sept. 29, 1966, 78,186; Aug. 11, 1967, 117,816 Int.Cl. B29f 3/00, 21/54 U.S. Cl. 264-177 4 Claims ABSTRACT OF THEDISCLOSURE The present invention relates to trilobal filaments, andspinnerets for producing the same.

It is already known in the textile industry to employ spinnerets inwhich the orifices have non-circular shapes, such as the triangular,square, rectangular or arcuate shapes with a view to obtaining yarns thecross section of which is a special shape differing from theconventional round or substantially round shape of the majority ofartificial and synthetic yarns. These yarns may for example have crosssections having the shape of a clover leaf, the letter Y, the letter X,the letter H or the letter C, or they may be substantially fiat orhollow.

It is an object of the present invention to provide a spinneret and afilament produced thereby having a novel and improved cross section.

It is a further object of the present invention to provide a spinneretcomprising at least one spinning orifice, each spinning orifice beingdefined by, in combination:

(a) three identical arcuate portions of a first circle, of diameter D,said portions being disposed 120 with respect to one another;

(b) two ends to each said arcuate portion;

(c) three pairs of lines;

((1) a first line of each pair extending inwardly of said circle fromone end of one of said arcuate portions;

(e) a second line of each pair extending inwardly of said circle fromthe other end of the arcuate portion adjacent to said one arcuateportion;

(f) the first lines of the pairs of lines being tangential to one innercircle concentric with said first circle, the second lines of the pairsof lines being tangential to said one or another inner circle concentricwith said first circle, the diameter d of said inner circle or circleslying between /6 and /3 of the diameter D of said first circle; and

(g) said first line of each pair intersecting said second line of anadjacent pair at an angle a of between 60 and 100.

It is still a further object of the present invention to provide a yarncomprising at least one trilobal filament, the cross section of which issubstantially that of an equilateral triangular core, and threesubstantially congruent triangular lobes, one apex of each of the lobesbeing coincident with a separate one of the apices of the core, and oneside of the triangular lobe lying substantially along a side of thetriangular core.

3,579,625 Patented May 18, 1971 The polymers utilized in carrying outthe invention include cellulose esters such as cellulose acetate orcellulose triacetate, or they may be synthetic polymer such aspolyhexamethyleneadipamide which can be melt spun, provided that theextruded filaments are cooled suddenly.

The spinneret of the invention may be utilized with any known device fordry or melt spinning. A spinneret furthermore may have any shape and anydesired dimensions being made from any material which is appropriate,having regard to the material which is to be spun. It may for example beplate shaped or cup shaped, and the orifices may be disposed in one ormore rings, or in one or more lines.

For use in the manufacture of cellulose ester filaments according to theinvention, the temperature of the spinning chamber walls should bebetween and 130 C., depending on the nature and volatility of thesolvent utilised and on the duration of the stay of the filaments in thechamber, i.e. in accordance with the spinning velocity and the length ofthe chamber.

The special cross sectional shape of the filaments produced according tothe invention impart special properties to them, in particular a highdegree of resilience, this being a quality which is particularlydesirable and appreciated in carpet pile and in other uses whichnecessitate a fiber of extremely high bulk. The special crosssectionalshapes may also be of interest when it is desired to produce an articlehaving a special appearance.

Other features and objects of the invention will become apparent fromthe following detailed description given merely by way of example,reference being made to the accompanying drawings, in which:

FIG. 1 is an underneath plan view of one embodiment of spinneretaccording to the present invention;

FIG. 2 is an enlarged schematic view of one of the orifices of thespinneret of FIG. 1;

FIG. 3 shows, to a considerably enlarged scale, the cross section of ayarn formed from five cellulose ester filaments extruded through aspinneret having five orifices the shape of each of which is asillustrated in FIG. 2; and

FIG. 4 shows, to a considerably enlarged scale, the cross sectionthrough a yarn comprising three synthetic polymer filaments extrudedthrough a spinneret having three orifices the cross section of each ofwhich is as illustrated in FIG. 2.

Referring now to the drawings, there is illustrated in FIG. 1, aspinneret 10, according to the invention, having nine orifices 11disposed in a circular array concentric to said spinneret.

Each said orifice 11 of the spinneret has the cross section illustratedto an enlarged scale in the schematic FIG. 2. Each orifice is thusessentially a circular orifice 12 into which project three triangularinserts 13, 14 and 15, spaced 120 apart around the circumference of thecircle 12, which has a diameter D.

Triangles 13, 14 and 15 are identical or congruent, and each includestwo straight sides 13A, 13B; 14A, 14B; and 15A, 15B, respectively. Thesides 13A, 14A and 15A are all, as can be seen from the figure tangentsto a smaller circle 16, which is concentric to circle 12, and has adiameter d. The diameter of circle 16 lies between Ms and /3 thediameter D, of circle 12. The lines 13B, 14B and 15B are also tangentsto the small circle 16, or to another circle (not shown) the diameter ofwhich also lies between /6 and /3 of the diameter, D of circle 12. Eachof these pairs of lines join at an angle a, which lies between 60 andThe orifice thus formed can thus be considered to be defined by threearcuate portions 17, 18 and 19, of the circle 12, and by the three pairsof lines 13A, 13B; 14A, 14B; and 15A, 15B.

ning chamber, and maintaining the walls of said spinning 3,418,200chamber at a temperature between 80 and 130 C. 3,419,936

4. The method defined in claim 1, wherein said textile filament ispolyhexamethylene adipamide.

925,732 References Cited 2 UNITED STATES PATENTS 1,303,379 2,843,4497/1958 Raynolds 264177Z 1,346,111 3,097,416 7/1963 McKinney 161177X3,117,362 1/1964 Breen 161177X 3,187,607 6/1965 Knammeck 264177Z3,303,530 2/1967 Cobb 264177Z 6 12/1968 Tanner 264177Z 1/1969 Sims264177Z FOREIGN PATENTS 5/1963 Great Britain 264177Z 10/1963 GreatBritain 264177Z 11/1965 Canada 264177Z 12/1962 France 264177Z 12/1963France 264177Z 10 JAY H. WOO, Primary Examiner US. Cl. X.R.

